Hygroscopic materials are generally difficult to handle. When the material is used in dry form it attracts water and thereby becomes sticky and difficult to treat mechanically. This limits the use of hygroscopic materials to use in wet or solubilized form. Use of wet materials at a distance from the place at which they are produced involves the transport of water which is considered as a wasteful process step.
A case in point is the use of lactose. Lactose (or milk sugar) is virtually the only sugar in milk. Lactose is a disaccharide composed of glucose and galactose. This sugar is present in cow milk at an average amount of 4.8% (w/w) and contributes to the nutritive value of milk and milk products, other sources for lactose are known. Lactose can be purified from milk or milk products. The most important source of lactose is the cheese industry. Lactose is an important component of whey permeate (about 80% lactose) which is a by-product of cheese manufacturing. Whey permeate therefore is considered as a very important nutritive product. Whey permeate is fed to animals or it is disposed. There is a growing tendency to valorize such by-products, especially in the form of animal feed.
In modern farming the feed given to animals is closely monitored with respect to its composition and nutritional value. Feed mixes are carefully prepared and the composition is varied with the species, age and physiological status of the animals. Lactose (in the form of whey permeate) which could be an interesting component of animal feed is hardly used due to its hygroscopic behavior. Dry feed compositions containing lactose become sticky and difficult to handle. Mixing of dried whey permeate together with other feed components also gives a hygroscopic product. The present invention solves this problem.